The drain is just for rain

This page contains guidance material for good stormwater management practices for small industries and businesses.

Every drop of rain that falls on our streets and doesn’t soak into the ground, ends up in the gutter and stormwater drains as stormwater. It then runs through an underground system of pipes and eventually flows directly into local rivers and creeks, untreated and unfiltered. 

It is against the law to place any material in a position that would allow it to flow into a local waterway and cause pollution.

The following recommendations should be regarded as complementary to safety plans, codes and licences required by authorities administering relevant legislation, such as the EPA, Local Councils, SafeWork NSW and Fire and Rescue NSW.

Chemical storage

The drain is just for water – chemicals, oils, paints and litter don’t belong there. Do not allow anything other than clean rainwater to enter the stormwater drain on or near your premises.

To avoid spills, leaks or discharges of chemicals down the drain, it is important to consider appropriate storage options for chemicals stored on your site.

These recommendations apply to the typical liquids found within many industrial and some commercial premises, including oils, solvents, fuels, acids and paints.

These liquids may also be characterised as Dangerous Goods under the Australian Dangerous Goods Code. Their use and storage must comply with the relevant guidelines.

Where should liquids be stored?

  • Store chemicals in closed, labelled containers
  • Store liquids in a designated area at your premises away from stormwater drains, preferably covered, sealed and bunded. This prevents any spills from contaminating the surrounding land or from entering stormwater drains.

It is important to check your storage areas regularly to make sure that there are no leaks or spills. If leaks or spills are found, they should be cleaned up promptly. Bunds should be emptied of liquid including rainwater as quickly as possible to maintain the capacity of the bunds. Liquids must be disposed of in a lawful manner.


A bund is designed to contain spills and leaks from liquids used, stored or processed above ground, and to facilitate clean-up operations. They are made from an impervious embankment of earth, or a wall of brick, stone, concrete or other suitable material, which may form part or all of the perimeter of a compound that provides a barrier to retain liquid. A bund should be large enough to contain the contents of the largest container, plus 10%. Bunded areas should be covered to prevent rain from entering.

The requirements for a bunded area vary according to the

  • type and volume of liquid being stored at the premises
  • level of risk at the premises
  • type of facility
  • type of drainage at the premises

Bunding doesn’t just apply to storage areas. It can also be placed across entrances to workshop areas and used to contain waste liquids. Speedhumps that are approximately 100mm high across the entrance to a workshop can turn the whole workshop into a bunded area. It is recommended that you paint bunds yellow for safety.

Facilities that should comply with bunding requirements include

  • Chemical storage facilities
  • Pesticide storage facilities
  • Petroleum storage facilities
  • Electrical transformers containing oil and/or PCBs
  • Facilities used to transfer stored liquids
  • Drum storage areas, either temporary or permanent
  • Processing areas
  • Transfer points
  • Workshops
  • Factories
  • Service stations
  • Wash bays

A number of Australian Standards provide further information on the construction, operation and maintenance of bunds, including minor storage, packing storage and handling, and storage in tanks.

Wash down areas

When undertaking any kind of washing activity, the runoff water must not enter any stormwater drains. Cleaning and washing activities including washing cars, equipment or work floors should be confined to a designated wash bay area, from which wastewater is

  • directed to a collection pit and then to sewer. This will require approval from Local Council via a Trade Waste Agreement
  • is treated and even recycled by the use of water treatment equipment

Wash down bays should be located away from drainage lines, stormwater drains and water bodies. All staff should be made aware that a wash down bay is available on site, and directed on when and how to use it.

Sediment and erosion control

It is important to manage sediment such as soil, sand, dirt and mud on your site. Sediment spills affect our environment and waterways by

  • Directly polluting our creeks, river and other waterways by filling them with dirt, soil, sand and mud. This leads to poorer water quality, affecting swimming or leisure activities in and around our waterways
  • Destroying aquatic habitats and smothering native plants and animals that live our waterways.
  • Blocking stormwater drains leading to flooding and overflows.
  • Eroding creek and river banks.
  • Causing health and safety risks such as slippery roads and tripping hazards.

Sediment and Erosion Control should include, but is not limited to

  • sealing hardstand areas to eliminate sediment in run-off
  • minimising exposed/disturbed areas on your site to limit the amount of dirty water generated in a rain event
  • diverting uncontaminated water away from your site
  • preventing material stockpiles from collecting or discharging sediment

General housekeeping

Everything we do in our homes and workplaces can affect the water that runs off our streets and ends up in our rivers. Remember to

  • always keep your site tidy
  • drop off old or unused chemicals to Community Recycling Centres
  • pick up any litter that has fallen on the ground after bin collection

Emergency reponse to spills

Spills should be cleaned up immediately by dry methods. Have a spill kit clearly labelled and easily available. Spill kits may include rags, brooms and mops, booms to contain larger liquid spills

Environmental management plans

Environmental Management Plans (EMP) are an important tool for managing your environmental responsibilities. An EMP demonstrates a commitment to maintain a responsible environmental process at your business. An EMP should include:

  • A comprehensive maintenance plan or schedule for your business processes on a daily basis.
  • Actions such as cleaning up and tidying work areas, cleaning the drains, waste removal, turning off valves and collecting waste liquids and containers.
  • Future improvements which are planned to improve environmental performance, such as new waste and storage areas. 
  • Staff training relating to clean-up procedures and environmental awareness

Minimising the risk of spills to the environment

The above recommendations are only a few of ways to minimise the risk of liquids entering stormwater drains. All employees working at sites with chemicals should know how to

  • do regular inspections of valves, pumps, pipes and hoses
  • use preventive maintenance
  • use standard operating procedures in the event of an on-site or off-site emergency
  • isolate a tank or bund
  • use fire-fighting equipment
  • stop substances entering the environment once they have escaped.

Other issues that you must consider when storing liquids include fire safety, storing compatible materials and restricting access.

Reporting your concerns

You can report any concerns in your community or notify your local council of any issues that need addressing  through Snap Send Solve,

Report pollution from motor vehicles and illegal dumping online and from your mobile phone with Report to EPA.

If you have any questions, or you are not quite sure what to do next, contact the EPA Environment Line at any time.
By phone: 131 555
By email:


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